Just MHO, but shots like this, with the item surrounded by white, look ungrounded to me, like the first paintings and sketches I did when I was first learning. We were always taught to put the items onto some solid object, for balance, perspective and grounding.
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There is definitely some truth to that. I think the white can work better for some objects, not so great for others. One thing I like is the conformity it gives the listings when scrolling through a seller's item list. While the grounded photos that you describe are nice when you're actually looking at them in full fize, I think the white background displays the item better when the photo is the size of an avatar, or slightly larger - which is how the listing would appear in search results.